US 2003/0146385 A1 · Method and apparatus for adjusting signal variation of an electronically controlled infrared transmissive window

Abstract

An analyte detection system non-invasively determines the concentration of an analyte in a sample generating a sample infrared signal indicative of the concentration of the analyte in the sample. The detection system includes a window assembly for receiving the sample infrared signal. The window assembly is adapted to allow the sample infrared signal to transmit therethrough, and generates a window infrared signal. The detection system further includes at least one detector configured to receive both the window infrared signal and the sample infrared signal transmitted through the window assembly. The detector is further adapted to generate a detector signal in response thereto. The detection system further includes a correction module configured to generate a corrected detector signal indicative of the concentration of the analyte in the sample.

Claims34

Dependent claims

An analyte detection system for non-invasively determining the concentration of an analyte in a sample, the sample generating a sample infrared signal indicative of the concentration of the analyte in the sample, the detection system comprising:

a window assembly for receiving the sample infrared signal, the window assembly adapted to allow the sample infrared signal to transmit therethrough, the window assembly generating a window infrared signal;
at least one detector configured to receive both the window infrared signal and the sample infrared signal transmitted through the window assembly, the detector further adapted to generate a detector signal in response thereto;
and
a correction module configured to generate a corrected detector signal indicative of the concentration of the analyte in the sample.

1 more element

A method for improving the sensitivity of a noninvasive infrared analyte detection system having a window assembly and a plurality of detector channels, each detector channel configured to generate signals in response to infrared emissions at a characteristic wavelength, the method comprising:

providing a reference detector channel, the reference detector channel configured to generate reference signals in response to infrared emissions at a reference wavelength;
measuring a reference window signal using the reference detector channel, the reference window signal having an amplitude corresponding to infrared emissions at the reference wavelength from the window assembly;
measuring a plurality of window signals using the plurality of detector channels, each window signal having an amplitude corresponding to infrared emissions at the characteristic wavelength of the detector channel from the window assembly;
calculating a scaling factor for each detector channel, each scaling factor equal to the ratio of the corresponding window signal amplitude and the reference window signal amplitude;
measuring a reference detector signal using the reference detector channel, the reference detector signal having an amplitude corresponding to infrared emissions at the reference wavelength from the sample and the window assembly;
measuring a plurality of detector signals using the plurality of detector channels, each detector signal having an amplitude corresponding to infrared emissions at the characteristic wavelength of the detector channel from the sample and the window assembly;
and
calculating a corrected detector signal for each detector channel, the corrected detector signal equal to the corresponding detector signal minus the product of the scaling factor and the reference detector signal from each detector signal.

5 more elements

Dependencies are inferred from the claim text.

Method and apparatus for adjusting signal variation of an electronically controlled infrared transmissive window

Life of this patent

Method and apparatus for adjusting signal variation of an electronically controlled infrared transmissive window

Life of this patent

Abstract

Claims34